TY - JOUR
T1 - Contrasting turbulence in stably stratified flows and thermal convection
AU - Verma, Mahendra K.
N1 - KAUST Repository Item: Exported on 2022-06-07
Acknowledgements: This paper is an expanded version (with some new topics) of the talk given at the conference Turbulence Mixing and Beyond 2017 organized at ICTP Trieste. I thank Snezhana Abarzhi and ICTP for hosting this interesting meeting. The numerical simulations presented in the paper were performed by Abhishek Kumar, to whom I am grateful. I am also thankful to K R Sreenivasan, Jorg Schumacher, Jayant Bhattacharjee, Joe Niemela, L Skrbek, Abhishek Kumar, Ambrish Pandey, Anirban Guha, Shadab Alam, Shashwat Bhattacharya, and other members of our turbulence group for useful discussions and idea exchanges. The simulations were performed on Shaheen II of the Supercomputing Laboratory at King Abdullah University of Science and Technology (KAUST) under the project K1052, on Chaos supercomputer of Simulation and Modeling Laboratory (SML), IIT Kanpur, and on HPC2013 of IIT Kanpur. This work was supported by the research grant PLANEX/PHY/2015239 from Indian Space Research Organisation, India.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
PY - 2019/4/9
Y1 - 2019/4/9
N2 - The properties of stably stratified turbulence and turbulent thermal convection are contrasted in this paper. A key difference between theses flows is the sign of the kinetic energy feed by buoyancy, FB. For SST, FB < 0 due to its stable nature; consequently, the kinetic energy flux Πu (k) decreases with wavenumber k that leads to a steep kinetic energy spectrum, Eu (k) ∼k?11/5. Turbulent convection is unstable, hence FB > 0 that leads to an increase of ?u(k) with k; this increase however, is marginal due to relatively weak buoyancy, hence Eu (k) ∼k?5/3, similar to that in hydrodynamic turbulence. This paper also describes the conserved fluxes for the above systems.
AB - The properties of stably stratified turbulence and turbulent thermal convection are contrasted in this paper. A key difference between theses flows is the sign of the kinetic energy feed by buoyancy, FB. For SST, FB < 0 due to its stable nature; consequently, the kinetic energy flux Πu (k) decreases with wavenumber k that leads to a steep kinetic energy spectrum, Eu (k) ∼k?11/5. Turbulent convection is unstable, hence FB > 0 that leads to an increase of ?u(k) with k; this increase however, is marginal due to relatively weak buoyancy, hence Eu (k) ∼k?5/3, similar to that in hydrodynamic turbulence. This paper also describes the conserved fluxes for the above systems.
UR - http://hdl.handle.net/10754/678672
UR - https://iopscience.iop.org/article/10.1088/1402-4896/ab022a
UR - http://www.scopus.com/inward/record.url?scp=85067191127&partnerID=8YFLogxK
U2 - 10.1088/1402-4896/ab022a
DO - 10.1088/1402-4896/ab022a
M3 - Article
SN - 1402-4896
VL - 94
SP - 064003
JO - PHYSICA SCRIPTA
JF - PHYSICA SCRIPTA
IS - 6
ER -